Persistence of protective immunity following vaccination against tick-borne encephalitis—longer than expected?

Delayed Humoral Immunity in a Patient with Severe Tick-borne Encephalitis after Complete Active Vaccination

“…Due to the fact that there is no specific antiviral agent available to treat TBE, prevention is the most important measure to diminish the individual as well as the public health impact of TBEV. Although in the vast majority of vaccinated individuals immunity persists for more than 3 years after a complete course of three vaccinations, about 7% of individuals older than 50 years show titers of neutralizing antibodies below 1:10 after 3 years, which calls their immunity into question [11]. Since the optimal time schedule for booster immunizations after complete or incomplete primary immunization is not known, currently large longitudinal prospective studies are conducted.…”

Response to tick-borne encephalitis (TBE) booster vaccination after prolonged time intervals to primary immunization with the rapid schedule

“…Studies on the persistence of antibodies after primary immunization with the conventional or rapid schedule and booster doses have shown higher titres in the younger adults when compared with the elderly (Beran et al, 2004;Rendi-Wagner et al, 2004b;Zent et al, 2004a). The GMTs (measured by ELISA or NT) before booster were lower in the elderly, and although the titre increase was higher for the elderly than for the younger adults, the post-booster GMTs were still higher for the younger adults (Beran et al, 2004;RendiWagner et al, 2004b).…”

Five year follow-up after primary vaccination against tick-borne encephalitis in children

“…The present study is thus the first to offer robust data demonstrating that antibody persistence following complete primary vaccination (either conventional or accelerated conventional schedule) with Encepur ® Children alone lasts for up to 5 years. While longer than expected antibody persistence (>3 years) has been reported in adults following primary immunization with three doses of FSME-IMMUN ® [21], this was not demonstrated in children receiving a mixed primary immunization series with FSME-IMMUN ® Junior and Encepur ® Children (two doses of FSME-IMMUN ® Junior and one dose of Encepur ® Children). The Encepur ® results, however, are in line with previous reports in both children and adults that have shown persistence of antibody responses for up to 5 years following booster vaccinations with Encepur ® [8,11,22,23].…”